Cyberpunk Rain Street: Terminal Velocity & Wet-Street Reflections (2D)

This 2D companion swaps the orbiting 3D camera for a flat, always-legible view of the same idea: light meeting water on a city street. Raindrops fall at their real terminal velocity — computed from the Atlas et al. (1973) empirical fit for drop diameter versus equilibrium fall speed, not a fixed constant — while a linear-reservoir hydrology model fills and drains a thin puddle film on the asphalt as you change the rain intensity and street drainage slope. Every neon sign reflected in that film is drawn at an intensity set by the Schlick approximation of the Fresnel equations, so a shallow viewing angle produces a bright, near-mirror reflection while a steep one lets the dry-looking asphalt show through — the same optical behaviour that makes real wet streets at night look the way they do.